This is not what the Jets signed up for when they signed Plaxico Burress as their prized offseason free agent acquisition.

This certainly is not what Jets fans envisioned, and it can’t be what Burress expected.

Six games into a season that was supposed to be a big, splashy comeback year for Burress after spending nearly two years in prison on a gun charge, he virtually has been invisible in the passing game.

Other than his blocking, which has drawn raves from coaches and teammates, Burress has been a non-factor. And let’s be honest, the Jets didn’t spend $3 million for his terrific blocking skills.

Considering his reputation as a big-play pass catcher and the fact he had fresh legs from two years of inactivity while behind bars, Burress’ lack of production is nearly as stunning as how poorly the Jets have played on both sides of the line of scrimmage this year.

Through six games, Burress has caught just 14 passes for 218 yards and scored two touchdowns. In fact, when Derrick Mason was traded last week for his supposed lack of production, he had the same amount of catches as Burress (13) — and Mason was a No. 3 receiver, not a starter like Burress.

Burress’ numbers average out to a paltry 2.3 receptions and 36.3 yards per game. The Jets could have similar numbers from some journeyman free agent who cost them half the money they are paying Burress.

Burress is on pace to catch just 37 passes for 581 yards for the full season. Suffice it to say the 6-foot-5, 232-pound target has not been the pass-catching beast the Jets expected.

“I’m not down on Plax,” Ryan said. “There’s going to be time when he has 10 catches [in a game], I truly believe that. It just seems like we’re missing just a little bit. I really think you’re going to see better chemistry and having the ball thrown to Plax more as the year goes on.”

To his credit, Burress, who has several drops and called himself out for them, hasn’t complained publicly about a lack of passes being thrown his way. He just hasn’t played up to the standards he’s set for himself.

In 2007, his last full season, Burress caught 70 passes for 1,025 yards and 12 touchdowns for the Giants. That was the year he almost single-handedly carried the Giants on his back in their NFC Championship Game win in Green Bay, where he caught 11 passes for 151 yards, and he caught the game-winning TD to beat the Patriots in the Super Bowl.

The Jets don’t need 11 catches for 151 yards every week from Burress, now at age 34, but they need more than the pedestrian numbers he’s been giving them.

Burress’ lack of production is certainly not all his fault. He’s trying to build a chemistry with quarterback Mark Sanchez, something that took Santonio Holmes some time to do last season. But it is curious why Sanchez doesn’t look Burress’ way more often considering how big a target he is.

Look at what Miami quarterback Matt Moore did with Brandon Marshall on Monday night. He threw a lot of designed back-shoulder passes behind Marshall, who was able to come back and make catches — even with the great Darrelle Revis covering him.

Why the Jets don’t do that with Burress is a mystery. Why Burress has not been featured more in the red zone, where he should be almost impossible to cover on fade routes, is a mystery.

Perhaps Sanchez — who is petrified of throwing interceptions, something that plagued him early in his career — simply hasn’t built that trust yet with Burress.

But the fact is the Jets are two games from the midway point of the season, and it’s time to take the vintage Ferrari out of garage, open it up and see what it’s got.